Method and device for operating a workstation of a cheese-producing textile machine

ABSTRACT

The present invention relates to a method for operating a workstation of a cheese-producing textile machine, having a pivotably seated creel for rotatably maintaining a cheese, a bobbin drive arranged on the creel, a support roller, which during the winding operation is driven by the cheese by frictional contact, a separate yarn traversing arrangement, as well as a device for raising the creel in case of a yarn break or a defined cleaning cut. In accordance with the present invention it is provided that following a yarn break or a defined cleaning cut, the cheese, which is maintained in the creel and rotated in the unwinding direction by the bobbin drive, and the support roller are sufficiently spaced apart long enough for a suction nozzle to pick up a top yarn required for a subsequent yarn splicing process.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of German patent application DE P 102 06 288.9 filed Feb. 15, 2002, herein incorporated by reference.

FIELD OF THE INVENTION

[0002] The present invention relates to a device and method for operating a workstation of a cheese-producing textile machine.

BACKGROUND OF THE INVENTION

[0003] Numerous methods or devices suited for depositing a yarn in criss-crossed layers on a winding bobbin have been known for a long time in connection with cheese-producing textile machines. Moreover, various devices are known which make it possible to raise a cheese off a driven winding drum, for example, in cases where there is a yarn break or a controlled cleaning cut. A winding device with the foregoing properties is disclosed in German Patent Publication DE 198 17 363 A1, wherein a winding drum is employed as a yarn traversing device.

[0004] In German Patent Publication DE 198 17 363 A1, the winding drum, which is provided with yarn guidance grooves, simultaneously drives the cheese rotatably seated between the arms of a creel by means of friction. If there is a yarn break or a defined cleaning cut, the creel and the cheese are raised off the winding drum and, subsequently, the cheese and the winding drum are braked to a halt. In this process, the yarn end of the top yarn runs up on the surface of the cheese as the cheese slows in its rotation.

[0005] In order to restart the winding process, this top yarn is picked up by means of a suction nozzle and is cleaned and connected with a bottom yarn in a yarn-splicing device. More specifically, the cheese initially is again lowered onto the winding drum and rotated slowly in the unwinding direction. Concurrently, a suction nozzle charged with a vacuum is pivoted into the area of the surface of the cheese. The suction nozzle pneumatically picks up the yarn end and places it into the yarn-splicing device, where it is connected with the bottom yarn as previously indicated.

[0006] In another embodiment of a winding device, for example, as disclosed in German Patent Publication DE 100 37 833 A1, the yarn traversing is performed by means of a finger yarn guide while the cheese is being directly driven. In particular, one of the two cone plates, which are rotatably seated in the creel, is directly connected with a drive mechanism. In this embodiment, the cheese rests on a freely rotatable seated support roller during the winding operation. The support roller is rotated by the cheese by means of a frictional connection. If there is a yarn break or a defined cleaning cut, the creel is first raised in a known manner, and the cheese is braked to a halt by the bobbin drive, which is charged with a braking current. As the creel is raised, the support roller is also braked by a special device.

[0007] Since the above-mentioned patents contain no suggestions as to where the creel, or the cheese, are positioned during the pick-up of the top yarn that has run up on the surface of the cheese, it can, therefore, be assumed that at this time the cheese again rests on the support roller in a customary way.

[0008] As previously indicated, the devices for raising a creel and a cheese from its winding drum or its support roller can have different embodiments. For example, a workstation of a textile machine is disclosed in German Patent Publication DE 195 34 333 A1, wherein the winding device has a winding drum, as well as a so-called creel relief arrangement.

[0009] This known creel relief arrangement is equipped with a damping cylinder which, when needed, can be charged with compressed air in a defined way by means of a controllable electromagnetic valve. After being charged with the compressed air, the damping cylinder then raises the creel such that the cheese can be raised off the winding drum. Since the cheese can only be rotated in the unwinding direction by the winding drum, which is absolutely required for picking up the top yarn, the cheese is lowered back onto the winding drum as soon as it has been braked to a stop.

[0010] Further, a workstation of a textile machine is disclosed in German Patent Publication DE 198 17 363 A1, wherein the winding device has a winding drum, as well as a creel, which can be raised by means of a so-called torque sensor. A drive element, preferably a step motor, is connected to the torque sensor. When required, the torque sensor can be definitely charged by an appropriate step-by-step adjustment of the drive element, and a torque can be applied to the creel. This means that the cheese can be purposefully raised off the winding drum through a defined introduction of this torque. As already described above, with this known arrangement the cheese rests on the surface of the winding drum during the pick-up of the top yarn and is rotated by the winding drum in the unwinding direction.

SUMMARY OF THE INVENTION

[0011] It is accordingly an object of the present invention to provide a method and a device that assures the gentle treatment of the surface of the cheese during the course of the pickup of a top yarn that has been wound onto the surface of the cheese after a yarn break or a defined cleaning cut.

[0012] This object is addressed by a method of operating a workstation of a cheese-producing textile machine, wherein each workstation has a pivotable creel for rotatably supporting a cheese for winding of a yarn thereabout, a drive associated with the creel, a support roller disposed for frictional driving by the cheese during winding of the yarn thereon, a separate yarn traversing arrangement, and a device for raising the creel upon a break or cutting of the yarn. The present method basically comprises the steps of maintaining the cheese in the creel following a break or cutting of the yarn, rotating the cheese in an unwinding direction by the drive, suctioning a broken or cut end of the yarn from the cheese in preparation for a subsequent yarn splicing operation, and spacing apart the cheese and the support roller via the raising device for a sufficient time for the yarn suctioning to be completed.

[0013] By means of the method of the present invention, it is assured that even with problem yarns the top yarn can always be pneumatically manipulated by the suction nozzle. Consequently, as has occurred often in the past, the top yarn is not pressed into the surface of the cheese such that it can no longer be picked up by the suction nozzle.

[0014] In accordance with one preferred embodiment of the present invention, during the pickup of the top yarn, the creel remains raised at least high enough so that a minimum distance is provided between the surface of the cheese and the associated support roller. The creel remains in this position, which is gentle to the surface of the cheese, until the winding process is started anew.

[0015] However, in an alternative preferred embodiment of the present invention, the creel is not raised when there is a yarn break or a defined cleaning cut, but instead the support roller is lowered and remains in this lowered position during the pickup of the top yarn. In this preferred embodiment, a minimal distance between the surface of the cheese and the support roller is also provided.

[0016] In yet another preferred embodiment of the present invention, it is also possible to position the creel during the pickup of the top yarn by the suction nozzle such that the surface of the cheese is clearly spaced apart from the associated support roller. Because of the change of the distance, which is maintained until the resumption of the winding process, it is possible to adjust the yarn-searching position of the suction roller. Thus, the method in accordance with this embodiment allows the yarn-searching position to be individually set and optimized in respect to the respective yarn parameters.

[0017] In a preferred embodiment of the present invention, the arrangement for executing the method of the present invention has a device which can actuate the creel by means of a so-called torque sensor. The torque sensor, which is connected to the pivot shaft, provides the creel with a predeterminable torque as the torque sensor is displaced in a defined manner by means of a drive element. The torque introduced to the creel by the torque sensor is preferably slightly greater than an oppositely acting calculable torque resulting from the innate weight of the creel, as well as the respective weight of the bobbin.

[0018] In a preferred embodiment of the present invention, the drive element for the torque sensor is preferably designed as a step motor. Because of their constructive design, step motors can be adjusted in very small steps, thereby allowing a sensitive setting of the torque to be introduced to the creel. Moreover, a step motor is a widely available, robust and cost-effective component.

[0019] In an alternative preferred embodiment of the present invention, the arrangement for executing the method of the present invention has the creel being raised by means of a pneumatic thrust piston gear. In this preferred embodiment, a damping cylinder arranged in the housing of the winding head is designed in such a way that it can be charged with compressed air by means of an electromagnetic valve. The electromagnetic value can be definitely controlled by the winding head computer. When required, the damping cylinder raises the creel and maintains it in this raised position until the spinning process is restarted.

[0020] Further details of the present invention can be taken from the following preferred embodiments, which will be explained with the aid of the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021]FIG. 1, is a schematic view of a winding device, in accordance with the present invention, with a drive mechanism for winding integrated in the creel, as well as a torque sensor for raising the cheese from the support roller and maintaining the cheese in this raised position; and

[0022]FIG. 2, is a lateral side view of a winding device, in accordance with the present inventions with a damping cylinder that can raise the cheese from the support roller and maintain it during the pickup of a top yarn that has run up on the surface of the cheese during the winding process.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0023] The preferred embodiment of the present invention in accordance with FIG. 1 represents a first embodiment of a workstation 1 of a cheese-producing textile machine.

[0024] It is known for such workstations 1 to have a winding head housing 2, on which a creel 5 is seated, pivotably movable, as well as a support roller 3, which is freely rotatable. The creel 5 is seated for limited rotatability, on a pivot shaft 6. As is customary, the creel 5 has two creel arms 7 and 8, each of which is provided with a rotatably seated cone plate. As can be seen from FIG. 1, a tube is held between the cone plates. A yarn can be wound onto the tube for forming a cheese 4. Moreover, a bobbin drive 20 is integrated in one of the creel arms 7, 8 of the creel 5, and acts on a connected cone plate of the creel 5 to drive the cheese 4. In the process, the cheese 4 itself rotates the support roller 3 by means of a frictional connection.

[0025] A torque sensor, identified as a whole by the reference numeral 30, acts on the pivot shaft 6 of the creel 5. In the preferred embodiment shown, the torque sensor 30 has, inter alia, a connecting disk 9, which is connected, fixed against relative rotation, with the pivot shaft 6. A gear wheel 10 is coaxially seated on the pivot shaft 6 and is rotatable in respect to the pivot shaft 6. The connecting disk 9 is provided with connecting bolts 11 that are pointed toward the gear wheel 10, which is provided with corresponding connecting bolts 12 directed toward the connecting disk 9.

[0026] Spring elements, in the preferred embodiment, helical springs 13, are inserted between the connecting bolts 11, the connecting disk 9 and the connecting bolts 12 of the gear wheel 10. In the course of a relative rotation of the gear wheel 10 and the connecting disk 9, the helical springs 13 are deformed in opposite directions and constitute the force transfer elements. The rotatably seated gear wheel 10 meshes with a pinion gear 14 of a reduction gear via a drive pinion gear 16. The outer rim 15 of the pinion gear 14 is connected to a drive element 17, preferably a step motor.

[0027] Since the drive pinion gear 16, the outer rim 15 and the pinion gear 14 are rotatably seated on the winding head housing 2, it is possible to transmit every rotating movement of the step motor 17, which is fixed in place on the winding head housing 2, to the gear wheel 10 via the reduction gear, for example at a ratio of 1:25. The step motor 17, which for example is designed for individual steps of approximately 1.8 degrees, is controlled by a winding head computer 18 through a control line 19. The step motor 17 can perform a predetermined number of revolutions or a predetermined number of individual steps which, by means of the torque sensor 30, result in a torque Mauf at the creel 5.

[0028] As can be further seen in FIG. 1, the workstation 1 additionally has sensors 23 and 24, which are also connected with the winding head computer 18 via appropriate signal lines 25, 26. The number of revolutions of the cheese 4, as well as the number of revolutions of the support roller 3, is continuously registered by means of these sensors 23, 24. From this data, as well as the known structural data of the machine and the existing yarn parameters, the winding head computer 18 always calculates the actual torque M_(ab), which results from the respective weight of the cheese 4, as well as the weight of the creel 5.

[0029] As schematically indicated, the workstation 1, furthermore, has a yarn traversing arrangement 21, as well as a suction nozzle 50. Yarn traversing arrangements 21, for example, finger yarn guides, are known, just as suction nozzles 50 for picking up a yarn end run up on the surface of the cheese 4 are known. Therefore, both devices need not be further explained in the following description.

[0030]FIG. 2 represents a lateral view of an alternative embodiment of a workstation of a cheese-producing textile machine in accordance with the present invention, wherein all components which are comparable with corresponding components in FIG. 1 have been provided with the same reference numerals. As can be seen, this workstation identified by the reference numeral 1 also has a winding head housing 2, which is represented partially open.

[0031] A creel 5 is seated in a customary manner and is pivotable to a limited degree on a pivot shaft 9. The creel 5 has creel arms 7 and 8. A cheese 4 is held in rotatable cone plates between the creel arms 7 and 8. As in FIG. 1, one of the cone plates in FIG. 2 is also directly engaged by a bobbin drive 20. As indicated and known from the preferred embodiment of the present invention in FIG. 1, the cheese 4 rests on a support roller 3 during the winding operation and rotates the support roller 3 by frictional contact.

[0032] A first lever element 28 of a creel relief arrangement, identified as a whole by 40, is seated, fixed against relative rotation, on the pivot shaft 6 of the creel 5. The lever element 28 is connected to the pivot shaft 6 via a connecting bolt 22, inter alia, to the piston rod head 27 of a damping cylinder 29. Moreover, a toothed element 32 is fastened via threaded bolts 31 on the lever element 28 and meshes with a corresponding toothed element 33. The toothed element 33 itself is fastened to a second lever segment 34 that is seated, rotatable to a limited extent via a pivot shaft 37, on the winding station housing 2. The lever segment 34 is connected via a weighting element 39, in a preferred embodiment, a tension spring, to an adjustment lever 41. In this case, the adjustment lever 41, which can be adjusted between the positions W, M and H, allows the defined presetting of the desired bobbin density of the cheese 4.

[0033] As can be further seen from FIG. 2, the damping cylinder 29, which provides a low-vibration running of the cheese 4 during the winding process, is connected to a compressed air source 44 through a pneumatic line 46, in which an electromagnetic valve 43 has been placed. The electromagnetic valve 43, which is preferably designed as a 2/2 directional control valve, can be definitely controlled via a control line 45 from the winding head computer 18 and, in the switched position represented in FIG. 2, the electromagnetic valve ensures that the creel 5 is pivoted into the yarn reception position I and is maintained there. In this yarn-searching position, the surface of the cheese 4 is clearly spaced apart from the support roller 3.

[0034] The operation of the winding device in FIG. 1 may thus be understood. In FIG. 1, if in the course of the winding process a yarn break occurs, or if a yarn cut is initiated by a yarn cleaning device (not represented), the winding head computer 18 first triggers the step motor 17 such that a torque Mauf is immediately applied to the creel 5 via the torque sensor 30. The creel 5 is pivoted slightly upward and in the process the cheese 4 is raised off the support roller 3. A braking current is simultaneously applied to the bobbin drive 20, and the cheese 4 is braked to a stop. The torque Mauf is preferably of such a size that at least a minimal distance “a” is set between the cheese 4 and the support roller 3. The cheese 4 remains set in this position slightly above the support roller 3 until the winding process is restarted.

[0035] Thus, in the customary manner following the raising of the cheese 4, a suction nozzle 50 is pivoted into the area of the surface of the cheese 4 while the cheese 4 is slowly rotated in the unwinding direction R by the bobbin drive 20. The suction nozzle 50, which is charged with a vacuum, pneumatically picks up the top yarn that has run up on the surface of the cheese 4 with its mouth, and moves the cleaned top yarn to a yarn splicing device (not represented) where the top yarn is connected with a so-called bottom yarn. If necessary, the suction nozzle 50 cleans the defective yarn section by means of a yarn cutting arrangement (not represented), and by means of an appropriate pivot movement.

[0036] The bottom yarn, which is derived from a feed spinning cop, is made available in a known manner by a so-called gripper tube, which has picked up the bottom yarn from a yarn tensioner and has also threaded it into the yarn splicing device. After splicing the two yarn ends, the regular winding process is started again. The cheese 4 is thereby lowered again onto the support roller 3 by an appropriate triggering of the torque sensor 30, and the bobbin drive is started. The driven cheese 4, which rests with a defined contact pressure on the support roller 3, then rotates the support roller 3 by frictional contact.

[0037] A comparable method is also followed when a winding device as represented in FIG. 2 is employed in accordance with the present invention. In FIG. 2, when there is a yarn break or a cleaning cut, the electromagnetic valve 43 is initially actuated via the control line 45 by the winding head computer 18. Accordingly, the electromagnetic valve 43, which is preferably embodied as a 2/2 directional control valve, is pushed into the switched position as represented in FIG. 2. Consequently, the annular space of the damping cylinder 29 is pneumatically and continuously connected with the compressed air source 44 via the line 46.

[0038] The piston rod of the damping cylinder 29, which is thereafter retracted, then pivots the creel 7 in the direction S until the creel 7 has been placed into the yarn receiving position I indicated by dashed lines. At the same time the cheese 4 is braked to a stop by charging the bobbin drive 20 with a braking current.

[0039] Following the braking of the cheese, the suction nozzle 50, indicated by dashed lines, is pivoted in a customary manner into the area of the surface of the cheese 4, which is positioned in the yarn pick-up position I, and the cheese 4 is slowly rotated in the unwinding direction R by the bobbin drive 20. With its mouth charged by a vacuum, the suction nozzle 50 grasps the top yarn which had run up on the surface of the cheese 4, cleans it and, as already explained above by means of the preferred embodiment of FIG. 1, places it into a yarn splicing arrangement, where the top yarn is connected with the bottom yarn. For restarting the winding process, the pressure in the damping cylinder 29 is subsequently removed, the cheese 4 is again lowered onto the support roller 3, and the bobbin drive 20 is started.

[0040] It will therefore be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention. Accordingly, while the present invention has been described herein in detail in relation to its preferred embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof. 

We claim:
 1. A method for operating a work station of a cheese-producing textile machine, wherein the work station comprises a pivotable creel for rotatably supporting a cheese for winding of a yarn thereabout, a drive associated with the creel, a support roller disposed for frictional driving by the cheese during winding of the yarn thereon, a separate yarn traversing arrangement, and a device for raising the creel upon a break or cutting of the yarn, the method comprising the steps of maintaining the cheese in the creel following a break or cutting of the yarn, rotating the cheese in an unwinding direction by the drive, suctioning a broken or cut end of the yarn from the cheese in preparation for a subsequent yarn splicing operation, and spacing apart the cheese and the support roller via the raising device for a sufficient time for the yarn suctioning to be completed.
 2. The method in accordance with claim 1, wherein, during the yarn suctioning, maintaining the creel raised to provide at least a minimum distance between the cheese and the support roller.
 3. The method in accordance with claim 1, wherein, during the yarn suctioning, maintaining the support roller lowered to provide at least a minimum distance between the cheese and the support roller.
 4. The method in accordance with claim 1, wherein, during the yarn suctioning, maintaining the creel clearly spaced apart from the support roller to allow a suction nozzle to optimally search for the yarn.
 5. A workstation device for producing textile cheeses comprising: (a) a pivotable creel for rotatably supporting a cheese for winding of a yarn thereabout; (b) a drive associated with the creel; (c) a support roller disposed for frictional driving by the cheese during winding of the yarn thereon; (d) a separate yarn traversing arrangement; (e) a device for raising the creel upon a break or cutting of the yarn, said raising device having a torque sensor connected to a pivot shaft of the creel; and (f) a drive element for controlling the torque sensor and the movement of the creel.
 6. The device in accordance with claim 5, wherein the drive element is a step motor.
 7. A workstation device for producing textile cheeses comprising: (a) a pivotable creel for rotatably supporting a cheese for winding of a yarn thereabout; (b) a drive associated with the creel; (c) a support roller disposed for frictional driving by the cheese during winding of the yarn thereon; (d) a separate yarn traversing arrangement; (e) a device for raising the creel upon a break or cutting of the yarn, said device having a damping cylinder connected with the pivotable creel; and (f) means for charging the damping cylinder comprising an electromagnetic valve controlled by a winding head computer. 